Vehicle gearbox

ABSTRACT

A vehicle gearbox ( 2 ) comprising a housing ( 4 ), wherein or whereon torque-transmitting components ( 14, 16, 18, 20, 30 ) are provided, comprising a coupling device ( 30 ) arranged between the vehicle gearbox ( 2 ) and a drive machine ( 8 ) driving the vehicle gearbox ( 2 ), wherein actuating elements ( 40, 46, 56, 60, 64, 66 ) are arranged in order to actuate the torque-transmitting components ( 14, 16, 18, 20, 30 ). The housing ( 4 ) comprises an area extending in the direction of the coupling device ( 30 ), wherein a connection plate ( 32 ), which can be firmly connected to the housing ( 4 ), is provided. Recesses are provided in the connection plate ( 32 ) for at least parts of the actuating elements ( 40, 46, 56, 60, 64, 66 ) for actuation of the torque-transmitting components ( 14, 16, 18, 30, 30 ).

This application is a national stage completion of PCT/EP2004/010291filed Sep.15, 2004 which claims priority from German Application SerialNo. 103 47 493.5 filed Oct. 13, 2003.

FIELD OF THE INVENTION

The invention concerns a vehicle gearbox.

BACKGROUND OF THE INVENTION

Vehicle gearboxes of modern design comprise a large number offunctionalities, which have to be accommodated in the housing of thevehicle gearbox. In the case of automated gearboxes, if the actuatorshave to be integrated in or on the gearbox, this makes its designelaborate and cost-intensive. At the same time, requirements relating toassembly methods appropriate for industrial practice must be fulfilledto make it easier for the assembler to combine together the individualstructural elements of the gearbox in a manner suited to the case whileavoiding assembly methods which are too complex and expensive.

To give an example, DE-Al 44 22 900 by the present Applicant shows avehicle gearbox with a connection plate which is attached firmly on thetransmission housing by screw-bolts and which is arranged in an area ofthe housing that extends toward a coupling device. On one of thecountershafts of the vehicle gearbox, a transmission brake is arranged,parts of which are provided in the connection plate. The arrangement ofactuating elements for actuating the torque-transmitting components inthe gearbox and the arrangement of a clutch actuator are not described.

The purpose of the present invention is to integrate actuating elementsof a vehicle gearbox at a central position in a manner appropriate forpractical assembly.

SUMMARY OF THE INVENTION

A vehicle gearbox comprises a housing in or on which torque-transmittingcomponents are provided. These also include a coupling device betweenthe vehicle gearbox and a drive machine which drives the vehiclegearbox. Actuating elements for actuating the torque-transmittingcomponents are arranged on or in the housing. The housing comprises anarea extending in the direction of the coupling device in which aconnection plate is provided that can be attached firmly to the housing.Lodgements are provided in this connection plate for at least parts ofthe actuating elements for actuating the torque-transmitting components.In an advantageous embodiment of the invention, a lodgement is providedin the connection plate for at least parts of an actuating device of thecoupling device between the drive machine and the vehicle gearbox.Preferably, the coupling device is a clutch with central disengagement.Particularly advantageously, the connection plate on the coupling deviceis made in the form of two tubes, one inside the other, and an actuatingpiston is arranged so that it can move axially in the annular spacebetween the tubes.

In a further advantageous embodiment of the invention, a lodgement isprovided in the connection plate for actuating elements that shift gearwheels of the vehicle gearbox into or out of a torque-transmittingcondition. Preferably, the actuating elements are parts of a shiftsystem of a main gearbox section and/or of a splitter group gearsetand/or of a range-change group gearset of the vehicle gearbox. Theactuating elements advantageously comprise pneumatic cylinders, one partof which is formed by the connection plate and one part of which isformed by the housing.

A vehicle gearbox of such design with a connection plate enables theadvantageous and assembly-friendly integration of many essentialcomponents and functional elements at a central location. Besides theclutch actuation and the actuation of the shift elements, at least partsof the transmission brakes and of the gearbox oil pump are provided inthe connection plate. The connection plate can be made independently ofthe remainder of the gearbox housing and is, therefore, easilyaccessible at any points for processing tools. Screw-bolts ensure simplefixing of the connection plate onto the housing during the assembly ofthe vehicle gearbox.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described, by way of example, with referenceto the accompanying drawings in which:

FIG. 1 is a cross-section through part of the vehicle gearbox, and

FIG. 2 is another cross-section similar to FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a vehicle gearbox 2 which comprises a housing 4. A driveinput shaft 6 is connected to a drive machine 8, as a rule an internalcombustion engine, and is mounted in the housing 4 to rotate in abearing 10. Mounted to rotate with the input shaft 6 is a gear wheel 12which meshes with a gear wheel 14 on a first countershaft 16 and with agear wheel 18 on a second countershaft 20.

Here, the invention is described with reference to the vehicle gearbox 2with power distribution to two countershafts. It retains its validity inthe same manner, however, for a gearbox with one countershaft.

The first countershaft 16 is mounted in a conical-roller bearing 22 inthe housing 4 and has a transmission pump 24 at one end which is drivenby the countershaft 16 for delivering lubricating oil to the gearbox.The second countershaft 20 is mounted in a conical-roller bearing 26 inthe housing 4 and has a transmission brake 28 at one end of the knownstructure which brakes the countershaft 20 and thus also the entirevehicle gearbox 2, and which is used, for example, during gearshiftprocesses. Around the input shaft 6, a coupling device 30 of knownstructure is arranged between the vehicle gearbox 2 and the drivemachine 8, which is not an object of the present invention and of which,here, only parts are, therefore, shown for illustrative purposes.

In the area of the housing 4 that extends toward the coupling device 30is arranged a connection plate 32, which is fixed firmly to the housing4, for example, by screw-bolts (not shown here). In a known way, theconnection plate 32 accommodates at least parts of the transmission oilpump 24 and the transmission brake 28. Furthermore in the area of theinput shaft 6, the connection plate 32 is shaped so as to form twoconcentric tubes 34 and 36, one inside the other. In an annular space 38between the tubes 34 and 36, an annular piston 40 is provided. Radiallyinward toward the tube 36 the said annular piston 40 has a first seal 42and radially outward toward the tube 34 the annular piston has a secondseal 44. The seals 42 and 44 seal the annular space 38 airtight withrespect to the surroundings, so that the annular piston 40 can be movedaxially by an actuation medium, preferably compressed air, admitted intothe annular space 38 so as to actuate a disengagement bearing 46 to openthe coupling device 30. Compressed air can be supplied directly throughthe housing 4, so that hoses and pipes for compressed air delivery arenot needed. Electrical leads for a path sensor (not shown here) on thecoupling device 30 can also be passed directly through the housing 4 orthe connection plate 32. To assist the movement of the annular piston40, an annular spring 48 is provided, which is accommodated in theannular space 38 between the annular piston 40 and the connection plate32.

The indexes used in FIG. 2 are the same as those of FIG. 1 forcorresponding components. Furthermore, FIG. 2 shows a first cylinderportion 50 in the connection plate 32 which, together with a secondcylinder portion 52 formed in the housing 4, constitute an actuationcylinder 64 for a shift device (not shown in any greater detail here) ina main transmission section of the vehicle gearbox 2. For this, in theactuation cylinder 64 formed by the two cylinder portions 50 and 52 isinserted an axially movable piston 54, to which is attached a gearshiftrod 56 which extends as far as the main transmission section. Thispiston 54 is also actuated by compressed air which passes into theactuation cylinder 64 through bores (not shown here) in the connectionplate 32 or the housing 4.

A sliding sleeve 58 is part of a splitter group gearset, which isconnected upstream from the main transmission section. The slidingsleeve 58 is actuated by a gearshift rod 60 connected to a piston 62.The piston 62 is arranged to move axially in an actuation cylinder 66and is actuated by compressed air, which can again be delivered to theactuation cylinder 66 through bores in the housing 4 or the connectionplate 32. A first cylinder portion 68 of the actuation cylinder 66 isprovided in the connection plate 32 and a second cylinder portion 70 isformed by the housing 4.

In a third cylinder (not shown here), another third piston can bearranged which, via a further gearshift rod, shifts the sliding sleeveof a range-change group gearset connected downstream from the maintransmission.

REFERENCE NUMERALS

-   2 vehicle gearbox-   4 housing-   6 drive input shaft-   8 drive machine-   10 bearing-   12 gear wheel-   14 gear wheel-   16 countershaft-   18 gear wheel-   20 countershaft-   22 conical-roller bearing-   24 transmission pump-   26 conical-roller bearing-   28 transmission brake-   30 coupling device-   32 connection plate-   34 tube-   36 tube-   38 annular space-   40 annular piston-   42 seal-   44 seal-   46 disengagement bearing-   48 annular spring-   50 cylinder portion-   52 cylinder portion-   54 piston-   56 gearshift rod-   58 sliding sleeve-   60 gearshift rod-   62 piston-   64 actuation cylinder-   66 actuation cylinder-   68 cylinder portion-   70 cylinder portion

1-9. (canceled)
 10. A vehicle gearbox (2) having a housing (4)incorporating torque-transmitting components (14, 16, 18, 20, 30) andincluding a coupling device (30) located on an input side of the vehiclegearbox (2) for connection with a drive machine (8) which drives thevehicle gearbox (2), the housing (4) having actuating elements (40, 46,56, 60, 64, 66) for actuating the torque-transmitting components (14,16, 18, 20, 30), a connection plate (32) is fixedly secured to thehousing (4) adjacent an area that extends in a direction of the couplingdevice (30), and the connection plate (32) having lodgements are for atleast parts of the actuating elements (40, 46, 56, 60, 64, 66) foractuating the torque-transmitting components (14, 16, 18, 20, 30). 11.The vehicle gearbox (2) according to claim 10, wherein a first lodgementis provided in the connection plate (32) for supporting at least aportion of an actuating device (40, 46) of the coupling device (30). 12.The vehicle gearbox (2) according to claim 10, wherein the couplingdevice (30) is a clutch with central disengagement.
 13. The vehiclegearbox (2) according to claim 10, wherein the connection plate (32)includes two tubes (34, 36), a first tube (36) is located inside asecond tube(34), and an actuating piston (40) is arranged to moveaxially in an annular space (38) between the two tubes (34, 36).
 14. Thevehicle gearbox (2) according to claim 10, wherein a first lodgement isprovided in the connection plate (32) for supporting the actuatingelements (56, 60, 64, 66) which shift gear wheels (14, 18) of thevehicle gearbox (2) into and out of a torque-transmitting condition. 15.The vehicle gearbox (2) according to claim 14, wherein the actuatingelements include parts of a shift system (56, 64) of a main transmissionsection of the vehicle gearbox (2).
 16. The vehicle gearbox (2)according to claim 14, wherein the actuating elements include parts of ashift system (58, 60, 66) of a splitter group gearset of the vehiclegearbox (2).
 17. The vehicle gearbox (2) according to claim 14, whereinthe actuating elements include parts of a shift system of a range-changegroup gearset of the vehicle gearbox.
 18. The vehicle gearbox (2)according to claim 14, wherein the actuating elements (56, 60, 64, 66)include pneumatic cylinders (64, 66), a first part (50, 58) of thepneumatic cylinders (64, 66) being formed by the connection plate (32)and a second part (52, 70) of the pneumatic cylinders (64, 66) beingformed by the housing (4).